Safe and Clean Web Browsing

The Internet provides a huge amount of information. The world wide web features many types of websites with all kinds of content, ranging from large text-based books to videos. A nice thing about the current state of PCs and internet browsers, is that it allows a good amount of customizing by the user. This customizing can make a great difference in web experience. This difference can be as large as a flashing page with annoying advertisements, compared to a quiet page with text-based content. It is important to block unclean content in order to respect the privacy of those who are abused in those images, and for the benefit of ourselves. Automated internet filters cannot really do this job, because the filter will either filter too much or too little, or both, locking out important web pages, or passing through unclean content. The only solution that can possibly work is that you yourself can decide which images to load selectively. In this article, I will describe how to configure the browser to hide all images by default, and how use this as a starting point to selectively load some or all images on a web site. Hiding all images by default might seem a rather drastic measure, but it is the only way we can really control which images will be loaded. Besides, many images on a web page are not really necessary. The images are mere decorations, or advertisements, while the main content is in the text. You are also saving a lot of bandwidth, because text takes only a fraction of the bandwidth of images, not to speak of video fragments.

Safety and security

Before we enter on the subject of browser configuration, it is important to make sure first that the PC is free of viruses. Computer viruses can interfere in many ways with web browsing, for example, by changing the start-up page, or by popping up advertisement windows, besides, of course, the other dangerous effects of computer viruses. How can viruses enter a PC? For example, when an infected CD is inserted in the PC, or when an infected web page is visited, or even when only being connected to the Internet. This is because most large software products contain security leaks which can be exploited by viruses. For these reasons, it is recommended to use good and up-to-date anti-virus software. It is also recommended to evaluate if a software product that you want to use is safe and secure, or if there are security or privacy problems. This is especially relevant for the web browser, because it is used to access the Internet. Should we always use the latest version of a software product? Although newer versions of software products often contain fixes of discovered vulnerabilities, they may also introduce new security or privacy issues, so it depends on the particular situation.

Web browser configuration

The two most used web browsers are Internet Explorer and Firefox. The configuration of these two web browsers are described separately in this article.

Web pages on the Internet can contain two types of images: normal images (such as JPEG pictures), and images that are displayed by a special plug-in or component. The normal images can usually be controlled easily. Both Internet Explorer and Firefox provide an interface for controlling the loading of images. The images in special plug-ins are different. Plug-ins are separate pieces of software that usually do not contain options to control the loading of images; plug-ins can either be activated or deactivated.

Configuring the Firefox browser

The Firefox browser provides many customization options. Because most of these options are hidden away in special places, it requires some technical knowledge to find them, but these things will be explained in the following sections as necessary.

Setting the start-up page

To change the start-up page of Firefox:

1. Open the Tools menu, and choose Options.
2. Click on the first section, titled something like General.
3. Edit the text in the Start-up Page edit box. To use an empty start-up page, type: "about:blank".

Deactivating plugins and similar components

Many images or animations are displayed from within plugins. For example, many advertisement banners are displayed by the plug-in called Shockwave Flash. To deactivate or deinstall plug-ins, a number of steps need to be taken. Some plug-ins can deactivated easily, while others require more effort.

Firefox provides a way to deactivate plug-ins:

1. Open the Tools menu, and choose Add-ons.
   A new window opens, where you view, activate, and deactivate extensions, themes, and plug-ins.
2. Select Plug-ins
3. Select a plug-in
4. Click the Disable button

For some other plug-ins or components, the following is needed:

1. In Firefox, type about:config in the address bar (where you normally type an Internet address), and press Enter.
   A message will appear that warns you to be careful
2. Type windowsm in the Filter-box.
3. Double-click on plugin.scan.WindowsMediaPlayer.
4. Type 100.0 as the value. (This is the minimal version of Windows Media Player that will be used as a plug-in. Typing 100.0 effectively deactivates the plug-in. The default value is 7.0.)

In the screen mentioned above, it is also possible to deactivate other components that can display images. You can search for a particular setting by typing the first few characters in the Filter box.

Dispite these adaptation, some plug-ins might still be active. To see if that is the case, and which plug-ins that are, open the special plugins screen:

1. In Firefox, type about:plugins in the address bar (where you normally type an Internet address), and press Enter.

The plugins screen shows you which plugins are active and which file it uses, which is a .dll file in most cases. A possible technique to disable a plug-in is to rename or move this .dll file that is mentioned in the "about:plugins" list. This renaming must be done while Firefox is closed. Other software that might be using these files, must be closed as well. Firefox will then not be able to find this plugin anymore, and will not use it consequently. Sometimes, however, a copy of the .dll is stored somewhere else, and it might be needed to also rename this other .dll file, in order to deactivate the plug-in.

Selectively enabling plugins

1. Open the Tools menu, and select Add-ons
2. Select Plug-ins
3. Select the particular plug-in
4. Select Enable

5. Do what you need to do with the plug-in enabled

6. Open the Tools menu, and select Add-ons
7. Select Plug-ins
8. Select the particular plug-in
9. Select Disable

In this way, you can enjoy the benefits of browsing without plugins, and at the same time be able to selectively enable it when visiting a specific web site, without much effort.

Not displaying images

The extension ImagePref provides an easy way to turn images on and off and to selectively load images. It contains features that are designed to make browsing without images more easy.

It is also possible to disable loading of images by hand, as follows:

• Open the Tools menu en choose Options.
• Select Content.
• Remove the check marker before Load images automatically.

This setting does not effect inline images. Inline images will still be shown as before. Inline images are typically small images that are contained inside a web page, instead of loaded externally as is the case normally. However, inline images are hidden by the extension ImagePref when images are off. This is a special feature of ImagePref.

When an image is not loaded, Firefox will display the alternative text instead. The alternative text is the text that the web page designer has specified. If you want to view a specific image, right-click on the alternative text, and select Load image (if you use ImagePref), or View image (when not using ImagePref). The option Load images is more convenient because it will load the image inside the original web page, instead of displaying it separately.

It is also possible to temporarily display all images. When using ImagePref, you can switch between all and no images with a mouse click on the Images checkbox in the lower right corner of the Firefox window. When not using Imagepref, undo the changes described earlier. It is sometimes necessary to refresh the page (F5). When you are done, you have to change it back manually, to hide the images again.

In Firefox, there is also the option to show only images from a particular web site:

1. Open the Tools menu en choose Options.
2. Select Content.
3. Leave the option Load images unchecked.
4. Click on the Exceptions button next to Load images.
   A window opens where you can add or remove web sites.

Hidden text

When the background image is not loaded, the text can become invisible when the text and the background have the same color. This can be solved sometimes by selecting the text with mouse, to make the text readable. When using ImagePref, right-click, and select Set white background, or Set black background depending on whether the text is black or white.

Configuring the Internet Explorer browser

Setting the start-up page

To change the start-up page in Internet Explorer:

1. Open the Tools menu, and choose Internet Options
   The Internet Options window appears.
2. Edit the text in the Start-up Page edit box. To use an empty start-up page, click on the button Blank page.

Deactivating plugins

1. Open the Tools menu, and choose Manage Add-ons (press the Alt key when no menu is visible)
2. In the Show drop-down box, select to view the installed plug-ins

In this screen, you can view which plug-ins are installed and deactivate them.

To temporarily enable plugins in Internet Explorer 7 or 8, use the Manage Add-ons screen, described above. After you have performed the work that required the use of a plug-in, you can disable the plug-in again.

Not displaying images

1. Open the Tools menu, and choose Internet Options
   The Internet Options window appears.
2. Click on the Advanced tab.
3. Scroll about 40% down.
4. Remove the check mark before Display images, Play animations, videos, (sounds,) etc.

When images are not loaded, a special placeholder rectangle is displayed instead. To load a hidden image, right-click on the placeholder, and select Display image.

Designers of a web pages have the option to supply alternative text for images. This alternative text is displayed inside the placeholder rectangle. If the size of the image is known, Internet Explorer displays a rectangle with the size of the hidden image. Sometimes the alternative text is not visible in Internet Explorer, because it does not fit in this rectangle. Then you can move the mouse over the image, and the alternative text will be displayed in a small yellow box.

Hidden text

When a background image is not loaded, the text can become invisible when the text and the background have the same color. This can be solved sometimes by selecting the text with mouse, to make the text readable.

Another way to view hidden text, that requires some technical HTML knowledge, is to open the HTML-source of the page:

1. Open the View menu, and select Source.

The hidden text is somewhere between the HTML-codes. A link starts with <a href="..."> (The destination location of the link is after href=), and a link ends with </a>.

General tips for both browsers

Images as links

Images are often used as links to other web pages. Because the image is not shown, it is less clear where the link points to, especially when no alternative text has been supplied by the web page designer. Of course, you could right click on the image to load it. But when there are many images, and many links on a page, this becomes cumbersome. As an alternative you can move the mouse on the hidden image. The link destination will be displayed (usually) at the bottom of the screen, on the status bar.

If a web site is not easy to navigate, because of hidden images, you could also try to use a search engine, and search for "site:<site name>". For example the search "site:www.palmwood-software.com grass" searches for all pages on this site where the word "grass" occurs.

Searching for information on the Internet

Sometimes we already know the address of a web site (an URL, such as http://www.palmwood-software.com) we want to visit, from an earlier visit, or from some other source. Sometimes, we only know that we want to know something about a specific subject. Then we often use a search engine. Link directories can also be helpful when starting to explore a new subject. It requires a bit of practice to effectively use a search engine. When entering some common search term, millions of pages will be found, and the probability that what we were looking for is at the top of the list will not be very large. For that reason, it is important to choose specific search terms. Try to search for words that will be used only in the document that you are looking for, or on the web site that you want to visit. If you do not know these words yet, you can try to search first with other words, in order to find the search words you need. It also helps to put the search terms between quotation marks ("...") if they must appear next to each other in the text. Search engine generally provide a short excerpt of the web pages that match the search query. It often shows much of the character of the site. When it is vague or chaotic, it is probably not a quality site.

Conclusion